The present invention relates to roll-up blinds or shades in general, and more particularly to a lateral pull roll-up blind or shade.
Various constructions of lateral pull roll-up blinds or shades are already known and in widespread use. For the sake of simplicity, reference will be had herein only to roll-up blinds, but it is to be understood that the present invention may also be employed in connection with roll-up shades and similar arrangements. Among the known roll-up blind constructions, there are such which include two carriers, a take-up shaft, an aperture member supporting one end of the take-up shaft and positionally fixable on one of the carriers, a drive including a driving wheel and an elongated pulling element trained about the driving wheel, plug-in entrainment elements which connect the driving wheel with the take-up shaft for joint rotation, a clamping arrangement which can be released by pulling on the pulling element, and a housing having an outlet opening for the pulling element and fixedly mountable on the other of the carriers.
A lateral pull roll-up blind of the above type is known, for instance, from the European patent application EP-A-No. 0086000. While it is true that this blind exhibits a sufficiently satisfactory operational performance while it simultaneously achieved a simple structure consisting of only a few parts, this is achieved only by the acceptance of substantial drawbacks. So, the clamping arrangement utilized in this known blind is constituted by a clamping shuttle which is movably supported in a chamber of the drive housing and through which there are guided the two runs of a pulling rope which is trained about a driving wheel that is accommodated in the drive housing. This has for its consequence that a chain drive consisting of a chain sprocket and a bead string, which is to be preferred in many instances for optical and functional reasons, cannot be used in this arrangement in view of the use of this particular kind of a clamping arrangement.
With a view to an optically appealing appearance, a quite high-weight rope tensioning member is typically being used in connection with the pulling rope, this tensioning member being hanged into the rope. The use of such a rope tensioning member is problematical when using the aforementioned clamping arrangement, inasmuch as there exists the possibility of an untimely loosening of the clamping.
While it is true that in this construction the take-up shaft, on the one hand, the drive, on the other hand, and the associated carrier are respectively complete operational elements in themselves, it is also true that in this known construction the connecting elements on the drive housing first of all, are situated outwardly of the circumference of the driving wheel and, secondly, are simply provided only in such a form that the drive can be mounted by means of its housing only in one spatial position on its carrier. Yet, there exists the desire on the part of the user for an arbitrary usability of one and the same system, that is, the possibility of mounting the blind on a wall or on the ceiling as well as in a niche, and also the possibility of arranging the drive at the right or at the left. The projection of the connecting elements, which in this construction also hold the two halves of the housing together, outwardly of the circumference of the driving wheel leads, considering the limited total amount of space which is available in systems of this kind for the drive and its housing, to a considerable dimensional buildup. As a result of this, but also in view of the quite weak clamping shuttle, an arrangement of this type can be used only for light and small roll-up blinds and, for this reason as well, the requirement for a highest possible degree of universality of use of such a system is not satisfied.
In another lateral pull roll-up blind of a similar construction, which is known from the German patent application DE-A-No. 3211506, while there is provided a clamping arrangement in which a stationary pin is surrounded by a clamping winding spring which is actuatable by the driving wheel of the drive, and while a chain sprocket cooperating with a bead string may be utilized in this construction, still the actual drive has a complicated construction which consists of a multitude of parts and, moreover, no actual housing is provided in this construction for the drive. Rather, the respective carrier is configured in a housing-like fashion. This structural and functional combination of the drive and of the carrier results only seemingly in a simplification of the construction. Yet in reality, with respect to the two ends of the roll-up blind, there results from this particular design approach a great number of various parts and, above all, the user is limited from the very outset by the required outlet opening in one circumferential or jacket wall of the carrier for the passage of the pulling element therethrough, with respect to the universal mounting possibility of the system, to a single possibility. The carrier can be utilized in this manner only at the right side or on the left side, depending on the chosen layout. Furthermore, also depending on the chosen layout, the carrier can be utilized only in a certain predetermined position, for instance, as a wall-mounted carrier. Herein, the support of the take-up shaft is also provided in such a manner that the take-up shaft can be introduced, for all intents and purposes, only from above. This means that a sufficient amount of free space must be left available in the upward direction in a system of this type so that, in the case of need, mounting of the system closely underneath a ceiling or another horizontal upwardly delimiting surface is not possible.
The conditions are similar in another lateral pull roll-up blind of the prior art which is known from the U.S. Pat. No. 4,424,851. In this construction, the driving transmission has an especially complicated construction which consists of a large number of different individual parts, yet the result is a reliable clamping of even relatively large roll-up blinds. Even here, there is not obtained a complete functional separation of the carrier and of the drive so that, once more, only the very limited utilization of the system for two predetermined cases of use, for example, as a wall carrier or as a ceiling carrier, results from this design, in conjunction with the connecting elements which are provided for use in only two positions.
In view of the fact that in this construction the drive is arranged at the exterior of the carrier, the mounting of the system in a niche is here impossible to begin with. The support for the roll-up blind is so constructed in this arrangement that mounting and dismounting is impossible without loosening and/or tightening connecting screws of at least one carrier.